A monolithic surface acoustic wave (SAW) signal processor which combines the functions of acoustic wave interaction, nonlinear product mixing, and integration, together with rapid-scan readout capability, which may be used, for instance, in correlation of amplitude and/or phase coded signals of a duration order of magnitude larger than the total propagation delay time of the SAW device, includes launching transducers at opposite ends of an interaction region, and a plurality of interaction taps, each tap comprising a Schottky barrier field effect transistor (FET), the sources and drains of the FETs being connected in common, but each FET gate being isolated. For long code correlation of a phase shift keyed signal, a reference wave having the same carrier frequency and identical coding is launched contemporaneously therewith in a first, correlation step, a standing wave component of product mixing of the two waves being of like sign or sense at any tap where the two waves are properly in phase integrating over the total number of code chips of the waves to provide an integrated, stored charge manifestation of correlation on the isolated gate of the related tap, the taps being interrogated for an integrated indication of correlation at one of the taps by means of a pulse of width the same as the propagation delay of a single tap mixing with an extended carrier at each tap, a component of product mixing at a third frequency (sum or difference) as a consequence of enhanced mixer efficiency due to the stored charge at the correlating tap, providing an output indication of the fact of correlation and phase relationship between the two waves. Various surface acoustic wave transducer and tap structures, utilizations, and implementation techniques are discussed.